The hazel dormouse Muscardinus avellanarius is predominantly found in the south and west of England and Welsh border counties. There are scattered populations further north and east. In the UK, hazel dormice are protected under Schedule 5 of the Wildlife and Countryside Act 1981 with additional protection as a European Protected Species.

Dormice usually live in well-established broadleaved woodland, particularly Ancient Semi-Natural Woodland. They can also be found in species-rich hedgerows scrub and coniferous plantations.



If a suitable hazel dormouse habitat is present on a site that falls within the known distribution range, further surveys may be required to determine their presence or likely absence. These usually take the form of nut and nest searches, and nest tube or nest box surveys.

Searches for nuts gnawed by dormice are best carried out during mid-August to December when fresh hazelnuts are present on the ground. If a nut search proves inconclusive, then a nest tube survey can be undertaken from April to November.

Survey calendar

Hazel Dormice survey calendar

ecology survey legend

If dormice are present

If dormice are found to be present via any of these survey methods then a European Protected Species Licence from the applicable Statutory Nature Conservation Organisation (SNCO), e.g. Natural England, and suitable mitigation and compensation measures are likely to be required in order to proceed.

Mitigation calendar

Hazel Dormice mitigation calendar

* Please note if a European Protected Species Mitigation (EPSM) Licence is required, the process can take some time and requires that recent survey work has been carried out at the site for this species. Survey work is seasonally constrained.

More information

Our ecology consultants have successfully delivered multiple projects with dormouse constraints and we have highly experienced and suitably licenced ecologists that can smoothly guide you through the planning process and help you achieve your desired outcome.

Contact Emma Mundy emma, to find out how we can help you.

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